Cristiano Ronaldo began another hugely satisfying evening's work by collecting the Golden Boot for his 42 goals last season and, after another fine demonstration of the art of scoring, it ended with his name being sung with more vigour than any other time since his summer dalliance with Real Madrid. There will always be some Manchester United supporters who struggle to forgive and forget but for as long as Ronaldo can strike this kind of fear in opposition defences he will inevitably succeed in winning over the majority.

Another two goals were served up here and if the Portuguese had not aimed his shot too close to Robert Green in the 89th minute Europe's most prolific scorer would have added another souvenir match ball to his collection. As it was, his goals had already settled the game on a night that will otherwise be remembered for West Ham's feeble resistance and the sheer brilliance with which Dimitar Berbatov, an Old Trafford hero in the making, set up the second goal.

The biggest compliment that can be paid to Berbatov is that, even in a stadium with the rich nostalgia and sepia-tinted memories of Old Trafford, it was difficult to remember a more sublime piece of penalty-area skill - even from Ronaldo. Sir Alex Ferguson used such adjectives as "stunning" and "magnificent" and nobody at Old Trafford will ever tire of seeing the television replays of how Berbatov deceived his marker, James Collins, to leave Ronaldo with an open goal.

Yet Ferguson was not altogether happy. Two up after half an hour, a thrashing might easily have materialised but, to the manager's irritation, his team eased off in the second half, despite playing the last 21 minutes with Ronaldo, Berbatov, Carlos Tevez and Wayne Rooney - a substitute - all on the pitch.

"The first half was magnificent and after that I was looking forward to more of the same," said Ferguson. "I was hoping they could add to their goals tally because that could be important at the end of the season. But they took their foot off the pedal and played at a couple of gears below what they are capable of. They ended up too lax for me."

The reason for that, perhaps, was that West Ham were so feeble that the players in red became bored with their own superiority. Ronaldo's first goal, for example, came in the midst of one of those extended spells when every West Ham player must have been enveloped by a deep sense of foreboding. Nani played the ball across the penalty area and Ronaldo was on to it in a flash, lashing a left-foot shot into the corner of Green's net. How would he celebrate? Old Trafford's amateur psychologists waited to analyse his body language and, after a dramatic pause of which Robert de Niro would have been proud, there was an explosion of unrestrained joy. Point made.

That was in the 14th minute and, from that moment onwards, Gianfranco Zola must have been hoping the final whistle could somehow be brought forward. The Italian won his first two league games after taking over from Alan Curbishley as manager but since then West Ham's form has plummeted. They also lost Valon Behrami to a potentially serious injury and their fourth consecutive defeat was all but confirmed when Berbatov's brilliance set up Ronaldo again.

The Bulgarian had done well even to keep Anderson's through-ball in play, reaching it only a few inches before it went out for a goal kick, but it was what came next which took the breath away. In one sublime movement Berbatov spun, pirouetted and danced away from Collins. The defender was still coming to his senses as Berbatov advanced towards goal and slid a beautifully weighted pass across the six-yard area. Ronaldo, alert as always, got there first, leaving Ferguson to eulogise about his £30.5m new signing.

"I'm going to have to see it again to understand how he [Berbatov] did it," the United manager said. "You'd pay double the money to watch that - fantastic imagination, control and balance."

Ferguson had made five changes from the team that drew 1-1 against Everton on Saturday, with Edwin van der Sar given the night off on his 38th birthday. His replacement, Tomasz Kuszczak, can be a danger to his own team sometimes but it was a measure of West Ham's performance that they did not force the Pole into a save until the final few minutes. This was as one-sided as they come.